As discussed in U.S. Pat. No. 6,472,006 for many food products, moisture levels must be maintained if the product is to exhibit optimum organoleptic properties, quality, and taste. Moisture migration in finished food products can seriously compromise quality, stability, and organoleptic properties. In addition, many chemical and enzymatic deteriorative reactions proceed at rates partially governed by the moisture content of foods. Excessive rates of these reactions can promote deleterious changes in the flavour, colour, texture, and nutritive value of food products.
In multi-component food products, particularly those having components with different moisture contents and water activities (e.g., pre-packaged cheese and crackers or pre-packaged bagel and cheese cream products), moisture can migrate between adjacent components, altering the component's characteristics and organoleptic properties. In addition to compromising the quality of finished food products, moisture migration can hinder production and distribution of food products. Thus, for example, the cheese in a cheese/cracker product could dry out while, at the same time, the cracker losses its crispness.
One method to prevent moisture migration in foods involves coating one or more surfaces of the food product with an edible moisture barrier. Such barriers should have a low moisture permeability in order to prevent the migration of water between areas of differing water activities. In addition, the barrier should cover the food surface completely, including crevices, and adhere well to the food product surface. The moisture barrier should be sufficiently strong, soft, and flexible to form a continuous surface that will not crack upon handling, yet can be easily penetrated during consumption. In addition, the barrier film's organoleptic properties of taste, aftertaste, and mouthfeel should be imperceptible so that the consumer is not aware of the barrier when the food product is consumed. Finally, the moisture barrier should be easy to manufacture and easy to use.
Because lipids, such as, for example, oils, fats, and waxes, are composed of lipophilic or water insoluble molecules capable of forming a water impervious structure, they have been investigated for use in moisture barrier films. With respect to oleaginous materials (i.e., fats, oils, sucrose polyesters, and the like) and/or other film forming lipids, it has been taught that, unless an undesirably thick coating is used, the barrier is not effective. Wax barriers have disadvantages as moisture barriers because they tend to crack upon handling or with changes in temperatures. Mixture of waxes with other components have been taught in the art, for example by Greener et al., 34-38, Lipid Technology, March-April 1992. However, these previously disclosed mixture also have suffered from the fragility problems of pure waxes such as beeswax.
The present invention alleviates problems of the prior art.